Tomographic imaging systems allow for high-resolution cross-sectional imaging in biological systems, and include, for example, optical coherence tomography systems, ultrasound imaging systems, and computed tomography systems. Tomographic imaging catheters allow for imaging of the subsurface of a lumen or vessel within the body, such as a blood vessel, through a minimally invasive procedure.
Typical tomographic imaging catheters consist of an imaging core, such as optical or ultrasound probes, disposed within a catheter that rotates and moves longitudinally through a lumen, while recording an image video loop of the lumen. The motion results in a 3D dataset, where each frame provides a 360 degree slice of the vessel at different longitudinal sections.
Prior to insertion of the imaging catheter to the target imaging area, a guidewire is directed into the lumen and retained at the target imaging area. The guidewire is typically a thin, flexible wire that is inserted into a lumen to act as a guide for subsequent insertion of the imaging catheter to the target imaging area. Once at the target imaging area, the imaging catheter rotates while moving longitudinally alongside the guidewire to acquire imaging data.
Because the imaging core rotationally sweeps past the guidewire during each rotation, the resulting images typically include a guidewire shadow or artifact that obscures imaging of tissue located behind the guidewire. The guidewire artifact is caused by the inability of the sensing energy, such as light or sound, to adequately penetrate the guidewire. The guidewire artifact is considered to be an unavoidable discontinuity in the imaging data that reduces image quality and can lead to misinterpretation of the resulting medical images.